Rope and the like



Patented June 2, 1936 noPE AND 'rn'E LIKE Sidney Albert Brazier andCecil Hampson, Manchester, and Melon Langstreth, Rochdale, England,assignors to Dunlop Rubber Company Limited, poration,

birmingham, England, a British cor- Appucation February' s, 1935,sei-ns1 No.A 5,052 In Great Britain February 23, 1934 9 Claims.

This invention relates to ropes and the like and particularly tonon-metallic ropes for use as drivlng belts.

Such rope as is-well known comprises a number of strands, each strandbeing made up of a number of cords andv each cord consisting of a numberof fibre threads or ends, for example, of hemp, sisal, manilla and thelike vegetable bres. i

To improve the driving qualities of such ropes, it is known for instanceto impregnate them with a mixture of graphite and grease but the fibrethreads on the outsiderof each strand of a rope so treated are vliableto fray due particularly to l5 the relative displacement'ofthe strandsto each y other when the rope exes, with the result that loose pieces ofbre containing the graphite and grease come oif and spoil the articlesand materials undergoing manufacture.

It is also known to make endless presser belts of rubberized fabric forvulcanizing machines.

A proposal has also been made to manufacture ropes, cords or the likefrom iilamentary or fibrous organic material impregnated with an aqueousVdispersion of rubber by treating certain of the yarns which are to beformed into a strand with rubber .latex which is used in such quantitythat when the treated yarns are, with other yarns which have not been sotreated, formed into a strand, the strand will be permeated orimpregnated to the desired extent with the latex or dispersion. l

The object of the present invention is to provide a rope. particularlyfor driving purposes, having a surface conditioned so as to obviate anytendency of the rope to slip and also having improved strength in thoseparts subject to most abrasive action.

It has been found to be -insuilcient merely to 40 rubberize with anaqueous dispersion of rubber the individual strands of a rope. On theother hand it was found to be unnecessary to make a rope from thread,individually impregnated with rubber derived from rubber latex becausethe inside of the strands of a rope are not subjected to any substantialabrasive action. It is the adjacent cords on the outside of the ropewhich are in the main subjected to this action.

According to the present invention, therefore. a rope, particularly fordriving purposes consisting of strands each of which is composed of anouter layer of cords surrounding an inner core of cords is characterizedin that each cord in the aforesaid outer layer of cords is composed ofrub- S Vbel'iined fibrous material.

Before'further disclosure of the present invention reference should bemade to the accompanying drawing wherein- Fig. 1 is a side elevationalview of the rope strand constructed in accordance with the pres- 5 entinvention; and l Fig. 2V is a cross-sectional view of the same.

In the drawing the outer layer of cords above referred to is identifiedby the word rubberized y and the inner core of cords above referred tois l0 identied bythe word unrubberized The cords in the aforesaid outerlayer can either be rubberized after their formation, or the cords canbe made from already rubberized threads. In the latter case, if desired,the cords made from 15 already. rubberized threads can be furtherrubberized after their formation.

Rubberizing of the aforesaid fibrous material forming the threads orcords of the rope is preferably effected by treatment with aqueous dis-20 persions of or containing rubber of the kinds hereinafter specified.

vThe cords in the inner core of each strand are preferably made of brousthreads but may ii desired consist of or contain a Ametallic core.

In a preferred method of carrying out the invention, the individualthreads are immersed in an aqueous dispersion. For example, fifty-foursuch threads are immersed simultaneously in the dispersion. It has beenfound possible toA obtain 30 sufficient penetration of the aqueousdispersion into each thread by merely passing the thread through thetank containing the dispersion. The fifty-fourl impregnated threads arethen assemb1ed into a cord. 35

Good results have been obtained by forming a rope from three strandseach of which comprises twelve outer rubberized cords produced as abovedescribed and twenty-one inner unrubberized cords. 4

In another method of carrying out the invention, wherein the cords arerubberized after their formation from unrubberized threads the cords areimmersed in a bath containing the aqueous dispersions aforesaid wherethey can be subjected, 4

.if desired, to mechanical pressure and release. The mechanical pressuremay be provided by rollers preferably V-grooved and mounted so as tomaintain a continual pressure on the material passing through. It ispreferable that the cords 50 should undergo more than one passagebetween vthe rollers. It is also desirable that the cords should beimmersed in the aforesaid dispersions vfor periods of not less than l5minutes priorto l the rst passage through the rollers. Drying oi i thecords after impregnation may take place in the stretched or unstretchedcondition.

The dispersions comprise those consisting of or containing rubber,gutta-percha, balata or similar vegetable resins occurring naturally orartificially obtained. i

Such artificialy aqueous dispersions mayinclude those of coagulatedrubber, vulcanized rubber, synthetic rubber, waste or reclaim. Ifdesired, any of 'the aforementioned dispersions may be sed alone or inadmixture with one another. Vulcanized aqueous dispersions can also beemployed.

Any of the aforesaid dispersions may contain the usual known compoundingingredients and/ or may be in concentrated form.

Concentrates such as are obtained in Patent 1,846,164 of February 23,1932, to which may be added any one or more of the usual compoundingingredients may also be used.

It has been found that mixings having concentrations of 35% orbelow arebetter for impregnation than more concentrated mixings.

It is desirable that the disperslons of rubber and the like shouldinclude vulcanzing ingredients and should also include anti-oxidentmaterials, as the ropes of the present invention may be subjected forlong periods to severe exposure conditions.

It is desirable that the aqueous dispersions employed should beconditioned to give rapid wetting of the cords. This can be effected bythe addition of wetting agents such as soaps in admixtureif desired,with caustic alkalies, yor alternatively by the addition of well-knownwetting agents used in the textile industry.

Having now particularly described our said invention, we claim- 1. Amethod of forming a rope which comprises rubberizing threads of iibrousmaterial, drying said threads, forming said rubberized threads intocords, laying said rubberized cords as an outer layer on an inner coreof unrubberized cords to form strands Without rubberlzlng said innercords, and assembling a plurality of said strands into a rope.

' 2. A method of making rope which comprises rubberizing cords, dryingsaid cords, assembling an outer layer of said dried rubberized cordsabout a core of unrubberized cords to form a strand and assembling aplurality of said strands into a rope.

3. The method `of forming a rope which comprises rubberizing threadscomprised of iibrous material, drying said threads, forming said'rubberized threads into cords, further rubberizing said cords, dryingsaid cords, assembling said rubberized cords as an outer layer on aninner core of unrubberized cords to form strands without rubberizingsaid innercords and assembling a number of said strands'to form a rope.

4. A method of forming a rope which comprises 'forming a plurality offibrous threads into cords,

impregnating said cords with rubber, drying said cords, assembling saidrubberized cords as an outer layer about a core of unrubberized cords 5I l from a plurality of said strands.

6. The method of forming a rope which consists in forming a plurality ofthreads consisting of fibrous material, impregnating some of saidthreads with rubber and drying the same, form? ing said impregnatedthreads and the unimpregnated threads into separate cords, impregnatingthe cords comprised of rubberized threads with 25 rubber to iill theinterstices between said threads and drying the same, forming a core ofsaid cords formed of the said unimpregnated threads, applying an outerlayer thereto of cords formed of the said impregnated threads obtainingthereby 30 a strand, and forming the said rope from a plurality of saidstrands.

'7. A rope consisting of a plurality of strands each of said strandsbeing comprised of a plurality of cords, said cords being arranged toform 35 an inner core of cords surrounded by an outer layer of cords,the cords of said outer layer being composed of brous materialimpregnated with rubber and the cords of said inner core being comprisedof fibrous material only. 40

8. A rope consisting of a plurality of strands each of said strandsbeing comprised of a plurality of cords, said cords being arranged toform an inner core of cords surrounded by an outer layer of cords,thecords of said outer layer being composed of a plurality oi threadseach of said threads being comprised of brous material lm pregnated withrubber.

9. A rope comprised of a plurality of Astrands 50 each of said strandsbeing comprised of a plurality of cords each consisting ofva pluralityof threads consisting of brous material, the cords of each 'of saidstrands being arranged to form an inner core of ,cords surrounded by anouter 5 5 layer of cords, the. plurality of threads oi" said outer layerof cords each being impregnated with rubber. i

